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My senior dog has dark liquid diarrhea with grass. Is it an emergency?

Updated On September 23rd, 2025

Pet's info: Dog | Great Dane | Male | neutered | 12 years and 10 months old | 165 lbs

I have a 13 yo great dane, male. Today he had diarrhea. It was dark liquid, with bits of grass. It was only the one time. His diet has not changed. Hey does take meloxicam daily and Ultram as needed for pain. His breathing is fine, gums are good color, resting well. Lab work was performed 2 months ago with his exam. All came back normal. His vet is closed today or I would have him there.

1 Answer

Most Helpful Answer

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Answered By Andrea M. Brodie, DVM

Veterinarian

Published on April 21st, 2018

If it is a one time occurrence I would not be too worried unless the feces were black (tarry), If that is the case immediately stop the meloxicam, as there may be a gastric ulcer caused by the NSAID. Keep giving the Ultram then. If the feces are black again the next time he does his business, Dexter will need to be seen by an emergency vet (PetER). If the color of the feces is more brown, then there is time to see the vet on Monday, and discuss the further administration of the Meloxicam. If it never was tarry or black, then your dog may just have had a bout of gastroenteritis, which only needs to be treated if the diarrhea does not go away within 2-3 days.

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